Presets are useful to initialize uninitialized /etc, but that doesn't
apply to the initrd.
Also, let's rename etc_empty → first_boot. After all, the variable
doesn't actually reflect whether /etc is really empty, it just reflects
whether /etc/machine-id existed originally or not. Moreover, we later on
directly initialize manager_set_first_boot() from it, hence let's just
name it the same way all through the codepath, to make this all less
confusing.
See: #7100
This function is really not a method of the Manager object (implemented
in manager.c), but just a helper in main.c. Hence let's not confusingly
name it the way methods are called.
We already made a similar change when talking about the "restart"
command, let's also do this for "systemctl reload" and friends.
Follow-up for: 6539dd7c42
See: #7126
Already, path_is_safe() refused paths container the "." dir. Doing that
isn't strictly necessary to be "safe" by most definitions of the word.
But it is necessary in order to consider a path "normalized". Hence,
"path_is_safe()" is slightly misleading a name, but
"path_is_normalize()" is more descriptive, hence let's rename things
accordingly.
No functional changes.
These three settings only make sense within the context of actual unit
files, hence filter this out when applied to the per-manager default,
and generate a log message about it.
These new settings permit specifiying arbitrary paths as
stdin/stdout/stderr locations. We try to open/create them as necessary.
Some special magic is applied:
1) if the same path is specified for both input and output/stderr, we'll
open it only once O_RDWR, and duplicate them fd instead.
2) If we an AF_UNIX socket path is specified, we'll connect() to it,
rather than open() it. This allows invoking systemd services with
stdin/stdout/stderr connected to arbitrary foreign service sockets.
Fixes: #3991
Let's make sure to process the fdname first, before changing the actual
input/output setting, since the fdname part can fail due to OOM.
This way we don't leave half-initialized bits around.
property_get_output_fdname() already had two different control flows for
stdout and stderr, it might as well handle stdin too, thus shortening
our code a bit.
Whether seccomp is supported or not is a server implementation detail,
the client should not be altered by that, and clients should be able to talk
to servers configured differently than the client, hence drop the
HAVE_SECCOMP ifdeffery here.
(This would be different if we'd need libseccomp or so to implement the
client, but we don't)
Both permit configuring data to pass through STDIN to an invoked
process. StandardInputText= accepts a line of text (possibly with
embedded C-style escapes as well as unit specifiers), which is appended
to the buffer to pass as stdin, followed by a single newline.
StandardInputData= is similar, but accepts arbitrary base64 encoded
data, and will not resolve specifiers or C-style escapes, nor append
newlines.
This may be used to pass input/configuration data to services, directly
in-line from unit files, either in a cooked or in a more raw format.
If the string length is specified as (size_t) -1, let's use that as
indicator for determining the length on our own. This makes it
slightlier shorter to invoke these APIs for a very common case.
Also, do some minor other coding style updates, and add assert()s here
and there.
All this function does is place some data in an in-memory read-only fd,
that may be read back to get the original data back.
Doing this in a way that works everywhere, given the different kernels
we support as well as different privilege levels is surprisingly
complex.
Mostly coding style fixes, but most importantly, initialize
c->std_input only after we know the free_and_strdup() invocation
succeeded, so that we don't leave half-initialized fields around on
failure.
Given that Linux assigns the same ioctl numbers ot multiple subsystems,
we should be careful when invoking ioctls, so that we don't end up
calling something we wouldn't want to call.
We are using the same pattern at various places: call dup2() on an fd,
and close the old fd, usually in combination with some O_CLOEXEC
fiddling. Let's add a little helper for this, and port a few obvious
cases over.
We currently use the ownership of the top-level directory as a hint
whether we need to descent into the whole tree to chown() it recursively
or not. This is problematic with the previous chown()ing algorithm, as
when descending into the tree we'd first chown() and then descend
further down, which meant that the top-level directory would be chowned
first, and an aborted recursive chowning would appear on the next
invocation as successful, even though it was not. Let's reshuffle things
a bit, to make the re-chown()ing safe regarding interruptions:
a) We chown() the dir we are looking at last, and descent into all its
children first. That way we know that if the top-level dir is
properly owned everything inside of it is properly owned too.
b) Before starting a chown()ing operation, we mark the top-level
directory as owned by a special "busy" UID range, which we can use to
recognize whether a tree was fully chowned: if it is marked as busy,
it's definitely not fully chowned, as the busy ownership will only be
fixed as final step of the chowning.
Fixes: #6292
Linux doesn't have faccess(), hence let's emulate it. Linux has access()
and faccessat() but neither allows checking the access rights of an fd
passed in directly.
Before this, assigning empty string to Delegate= makes no change to the
controller list. This is inconsistent to the other options that take list
of strings. After this, when empty string is assigned to Delegate=, the
list of controllers is reset. Such behavior is consistent to other options
and useful for drop-in configs.
Closes#7334.
This option is likely to be very useful for systemd-run invocations,
hence let's add a shortcut for it.
With this new concepts it's now very easy to put together systemd-run
invocations that leave zero artifacts in the system, including when they
fail.
Right now, the option only takes one of two possible values "inactive"
or "inactive-or-failed", the former being the default, and exposing same
behaviour as the status quo ante. If set to "inactive-or-failed" units
may be collected by the GC logic when in the "failed" state too.
This logic should be a nicer alternative to using the "-" modifier for
ExecStart= and friends, as the exit data is collected and logged about
and only removed when the GC comes along. This should be useful in
particular for per-connection socket-activated services, as well as
"systemd-run" command lines that shall leave no artifacts in the
system.
I was thinking about whether to expose this as a boolean, but opted for
an enum instead, as I have the suspicion other tweaks like this might be
a added later on, in which case we extend this setting instead of having
to add yet another one.
Also, let's add some documentation for the GC logic.
Lennart Poettering